Test the hypothesis that intravenous (IV) IGF-1 administration enhances brain parenchymal reorganization and thereby improves neurologic outcome. Test the hypothesis that IV IGF-1 administration decreases hyperglycemia, decreases brain lactic acidosis, and prevents secondary brain injury from acidosis. Test the hypothesis that IV IGF-1 administration prevents the catabolic sequelae to injury, preserves normal blood amino acid ratios, decreases excitotoxic amino acids presented to the brain, and thereby improves recovery.